KINE3440 Lecture 1: Neural Transmission PDF
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This document describes the different types of neural transmission, including direct and indirect control of movement, and explores the differences between white and grey matter. It also details functional nerve divisions, concepts of the PNS and CNS, and discusses various types of axons, neurotransmitters, and their roles. The document serves as lecture notes for a course in kinesiology or a related field.
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Direct vs indirect control of movement - Direct is sensation = movement - Indirect is sensation = brain cognition = movement White matter vs grey matter Type White matter Grey matter ------------- ----------------------...
Direct vs indirect control of movement - Direct is sensation = movement - Indirect is sensation = brain cognition = movement White matter vs grey matter Type White matter Grey matter ------------- ------------------------------------------------------------------------ ------------------------------------------------------ Myelinated? Yes No In PNS Tract Nucelus In CNS Nerve Ganglion Function Communication between different brain regions and brain to spinal cord Processing info, sensory perception, decision-making Functional nerve divisions - Somatic - Spinal cord to body - Voluntary - Automatic - Spinal cord/brainstem to smooth muscles - Regulatory - Cranial - Brainstem to head/neck - Special senses - Voluntary PNS Concepts - Spinal nerves - Spinal roots origin (31 pairs) - Plexus - Mixed motor/sensory - Cranial nerves - Brainstem origin (12 pairs - Some sensory - Some motor - Some mixed CNS Concepts - Tract vs nucleus - Transmission vs control - Decussation - Crossing midline Brainstem - Medulla - Arousal, respiration - Pons - Posture, balance - Midbrain - Orienting Cerebellum - Motor function - Cognitive functions Cerebrum - 2 hemispheres - Grey and white structure Cortex - Brain lobes - Complex functions - Sensory, motor, etc Meninges - Surround CNS - Dura mater, pia mater, arachnoid mater Stem cells - Progenitor cells - Undifferentiated - Can grow to neurons if pushed Glial cells - Macroglia - Astrocytes - Oligodendroglia - Schwann cells - Microglia - Phagocytes (immune system) Local Potential - Where - Dendrites or soma - What - Excitatory- depolarize - Inhibitory- hyperpolarize - How - Ion channels open to allow either more Na (depolarize) or K/Cl (hyperpolarize) Integration of action potential - What - Triggered response - Action potential - Where - Voltage-gated channels (axon hillcock most important) - How - Opening/closing of ion channels Myelinated axons - Saltatory conduction - Fast, low energy cost - Process 1, under myelin - No voltage-gated ion channels - Passive current flow - Process 2, nodes of ranvier - Voltage-gated ion channels - Action potentials Demyelinated axons - Exposed axon - Acute - No voltage-gated channels - No insulation - Chronic - Voltage-gated channels develop - Becomes like unmyelinated Unmyelinated axons - One component - Voltage-gated ion channels - Action potentials along entire axons - High energy cost Pre-synaptic neurotransmitters - Synthesized in soma - Release - Voltage gate Ca channels - Action potentials - Diffusion to post synaptic membrane Post synaptic NT effects - Metabotropic receptors - G-protein activation - Can produce diverse effects Acetylcholine - Major role in PNS - Neuromuscular junction - Autonomic nervous system - Some role in CNS Glutamate - Primary excitatory NT in CNS - Plasticity - Excitotoxicity GABA - Primary inhibitor NT in CNS - Clinical features
